18398921375 has 16 divisors (see below), whose sum is σ = 23351047200. Its totient is φ = 14469654400.

The previous prime is 18398921363. The next prime is 18398921393. The reversal of 18398921375 is 57312989381.

It is not a de Polignac number, because 18398921375 - 2²⁶ = 18331812511 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 18398921375.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1240010 + ... + 1254759.

It is an arithmetic number, because the mean of its divisors is an integer number (1459440450).

Almost surely, 2^18398921375 is an apocalyptic number.

18398921375 is a deficient number, since it is larger than the sum of its proper divisors (4952125825).

18398921375 is an equidigital number, since it uses as much as digits as its factorization.

18398921375 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2494843 (or 2494833 counting only the distinct ones).

The product of its digits is 3265920, while the sum is 56.

The spelling of 18398921375 in words is "eighteen billion, three hundred ninety-eight million, nine hundred twenty-one thousand, three hundred seventy-five".